Emily starts counting at 40, and she counts by threes. If 40 is the 1st number that Emily counts. what is the 14th number that she counts?
Solution: What is the first number that she counts? $40$ What is the second number that she counts? $\begin{align*}&40 + 3 \\ &= 43\end{align*}$ What is the third number that she counts? $\begin{align*}&40 + 3 + 3 \\ &= 40 + (2 \times 3) \\ &= 46\end{align*}$ What is the 14th number that she counts? $\begin{align*}&40 + (13\times3) \\ &= 40 + 39 \\ &= 79\end{align*}$